Sunday, 17 August 2014

Millwheel turning

The Moulin du Gô at St Pierre sur Erve is being renovated, and they have got the water wheel to work. This has involved completely remaking all of the oak sections of the wheel including the paddles and spokes, and getting the whole thing central on the axis. It's still not quite central and the wheel speeds up and slows down just a little as it turns, but it's pretty even. The centralising is achieved by hammering different-sized bits of wood between the metal hub and the oak shaft. You can see them on the shaft as it turns. I gather it's very much a trial-and-error thing to get right.

There is more work to be done in the next room. You can see that this horizontal wheel is not square on to its axis, so that will need sorting out. It also has no gear teeth, and it requires an especially hard wood; what the French call a Cormier; Sorbus domestica, a rare tree in Europe. They were lucky - they found some at a furniture-maker's in the village, and he is making the gear teeth. Once they are in place, they will be able to turn the millstone that is upstairs.

The wooden teeth that are already in place on the vertical gearwheel are made from Robinia pseudoacacia, a hard wood that is strong enough for this application but not for the smaller wheel.

They reckon that the wheel will generate about 9 horespower, which is a bit less than 7 kilowatts. If it were up to me, I'd hook in an electric generator, back it up with solar panels in Summer in case the river gets low, and Bob's your uncle: free electricity for life.

3 comments:

Helen Devries
said...

Super project. We looked at a watermill with a turbine system in place...but EDF wouldn't accept the electricity generated as it fluctuated...and so the previous owner spent every winter with the windows open and all the lights on...

I'll bet that water-powered electricity doesn't fluctuate nearly as much as solar. Clouds blot out sunlight as they move past the sun, and sunlight also has a well-known tendency to disappear completely at night. I am unaware of any tendency of rivers to dry up at night, nor for them to have wave-like phenomena that would cause the sort of fluctuations that clouds make.

I think it's probably because of the subsidies available for solar: if EDF paid individuals for hydro what they are obliged to pay for solar, they'd go bust.

Me

By a beautiful river valley in North-West France. This blog is about the day-to-day events in running a group gîte in Mayenne. There's a lot of gardening, maintenance, but, I hope, a lot of fun too.
Best viewed in widescreen format.
This website uses cookies. By browsing this website with cookies enabled, you are agreeing to their use.